I've gained so much from Head-Fi that I figure I'll give back a bit with a review.

About two months ago, I was in the Orient where I spent a few days at headphone pro shops testing out various headphones. It was very illuminating. On the upper end, I tested the top end of the likes of the Sennheiser HD800, Beyerdynamic T1, Grado RS1 etc. In the end, my favorites were the HD800 and HD650 though both are a fair bit different. The HD800 had an incredible clarity and huge precise soundstage. The HD650 had a nice warm relaxed tone, and yet lots of detail though with a more intimate soundstage. I also liked the Philips X1 which was a fun bass oriented fast headphone and easy to drive. I did like the AKG Q701 for its large soundstage but the instrument placement is very indistinct. (Someone had likened it to having music in an airplane hanger.) It really is amazing how distinct the differences are from

When I returned, I ended up with a HD650 and a loaner Q701.

Noodling around the web, especially Head-Fi, I was intrigued by comments on the modified Fostex T50RP.

So I chat with a few T50RP modders who sells them online. In the end, after a fair bit of research, I went with a gentleman who posted some sets on Ebay by ZMF. Turns out these are also sold directly online. In truth, i really did not expect much given its base price. I am posting here because the results greatly exceeded my expectations and I figure others may be interested in my observations. Note that I am on the road but will take photos when I get back and post here.

Also note that in the end, I compared TWO versions of ZMF's modded T50RP as explained below.

1. RESOLUTION & SPEED. This blew me away with heaps of resolution across the entire frequency range over the HD650 and Q701. But without any additional fatigue. I would say the high is very clear and sweet rather than sharp. Often, a lot of high-resolution headphones seem fatiguing to me as they accentuate the highs. But with this, I can simply hear a lot more detail. It also felt very fast compared to the other two. I think this contributes to the sense of resolution. I simply hear so much more detail! Without having the HD800 here, my first impression is 'Whoa! This sounds like the HD800 in clarity/detail/speed but without that huge soundstage and perhaps less bass." This thoroughly surprised me.

This difference is incredibly distinct when A/B between the T50RP and either the HD650 or Q701. Again, emotively it felt like the difference I felt between the HD650 and HD800 when swapping the two though the T50RP does not have the soundstage width of the HD800. For me, this is not faint praise.

2. Physical quality. These just feel SOLID. Feels a lot more than the $180 charged. It came with a padded leather headband that I see on Amazon.

3. Soundstage is narrower than the HD650, and certainly less than the Q701. These are semi-closed. However, it has more soundstage width than other closed headphones if my memory serves. This is fine for more intimate pieces.

Areas that I did not like as much.

1. By far, the top for me is the somewhat recessed bass. I have pieces that I know well and have heard through many systems. As mentioned, I listen at low to medium low levels to protect my ear so the perception of bass response is also reduced compared to someone who listen at higher volume. The HD650 and Q701 simply have more bass than the version 1 T50RP. The T50RP bass is there - just less.

But I really liked the speed and resolution of this modded T50RP so I did something that I normally do not do. In Spotify, I used EQUALIFY equalizer to boost the bass 3db at 60hz, 170hz and then slope down to zero at 1000hz while passing through 310 and 610 on the slope.

Wow! This made a world of difference! It was wonderful with the bass boost - no loss of clarity and speed. So for me, 3 db made a difference as I have this HD650 sound in my head.

My problem of course is that I really loathe to use EQ for my speakers and headphones. I have so many players (Ipad, laptop, home system etc) that I rather not hassle with EQs. So my headphones need to stand alone without EQ.

Because this unit feels so fast, the lack of bass is accentuated. With the HD650 which feels slower, there is a bit of a lingering of the bass which adds to the sense of a full bass.

2. The soundstage is just noticeably smaller than the Q701 and HD650. HD650 sounds about average in soundstage for open headphones. So for more intimate pieces, its OK. But for larger works, it fells cramped to me and artificial because of that. The open headphones simply feel more natural though the Q701 is too diffused, more like in a plane hanger - but for some large orchestral pieces, this actually works to its advantage.

#1 and #2 are the top reasons why I found it harder to loose myself in some music. #1 I can probably change but #2 is what it is.

3. Semi-closed.

I prefer open headphones because I want to hear the environment around me at home so that I am not isolated from my dear wife and children. But this is not a critique as closed and semi-closed headphones are a valid approach. This is simply my preference.

4. The stock cord's 1/4" plug was a bit wiggy. Occasionally, I would not have the left channel when plugged and I have to wiggle the plug a bit. But it is rare - just a few times during my testing out of dozens and dozens of switches. This has not happened to any of my other 1/4" plugs with three headphones so I think my amp output jack is fine.

DECISION: In the end, though it sounded fantastic with EQ, I told Zach (of ZMF) that I rather have headphones run flat without EQ. That's when ZMF mentioned that he has a version 2 that is bass boosted. He wondered if I would be interested in that instead. I said yes and shipped my first pair back.

Version 2 Comments

1. Clearly does have more bass. I did not feel the need to use EQ to boost the bass.

2. It also sounds much closer to the HD650 in tone, clarity, and speed. I did not have the sense of 'Wow- what an incredible difference!' though it was still clearer the HD650.

3. Zach used a modded recycled leather strap to provide a support similar to the AKG Q701. (Photo to follow.) I liked this more than version 1 because I have a bump on my head and this strap conforms better.

After some hours, felt that version two was in between version 1 and the HD650. Compared to version 1, it seemed to have more bass, has a thicker tone, slightly less clarity and speed. However, I do not trust my memory and wished that I had version 1 to compare as I did not trust my memory. So Zach shipped version 1 back to me. (Yes, I'm paying for shipping both ways.)

Version 1 and Version 2 Side by Side.

1. Version 1 has less bass, is definitely clearer, faster and leaner in the tone. It has better apparent resolution.

2. Version 2 has more bass and fatter in tone. However, though I observe it as slower and less definition than version 1, note that it easily matches the HD650 so it is not at all lacking. It is just that version 1 has gobs of clarity.

3. Interestingly, version 2 is louder than version 1. Perhaps it's just in the bass? My amp has a digital volume setting and when I turn up version 1 by 2db, the two sound about the same volume loudness. Zach confirmed that version 2 is indeed louder due to how he modifies them. Apparently version 2's drivers are less restricted.

4. KEY: I increased the bass by EQ on version 1 and expected it now to sound more like version 2 with lesser apparent resolution and less speed. However, this was not the case at all. The version 1 actually gained more bass punch BUT maintained the edge in clarity and speed. Wow - a surprise here. The bass notes have huge amount of definition and speed.

5. In conclusion, if version 1 and HD650 are opposite end of the poles, then version 2 is in the middle. The difference between HD650 and version 1 when swapped is very obvious. But HD650 and version 2 when swapped, is more similar.

6. Headband. When Zach reshipped the version 1, he upgraded the head padding to a very plush deluxe Pilot band that is wider, softer and much plusher than the original. Very nice. I took it off to find it very lightweight - almost feather weight at 1.4 oz. It really added a luxurious feel. Personally I am still going with the recyled leather band simply because it is thinner, smaller and I have that pesky bump on my skull….:)

CONCLUSION

My recommendation:

1. If I wanted just one headphone and no EQ, I would pick version2.

2. If I wanted just one headphone but happy to add EQ, then it is a toss up between version 1 and version 2. Some would prefer the version 2's fatter tone.

3. If have other headphones such as the HD650 and wanted a bit more contrast, I would go with version 1.

In the end, I kept the version 1, changed my mind about EQ and used the EQ with these. They are good enough to persuade me to change my behavior. With EQ it still maintains that incredible resolution all the way to the lower bass. f

In short, these easily hold their own against the much more expensive Sennheiser HD650 and AKG Q701. (Note that I prefer the HD650 over the Q701.) Of all the headphones I tested on my trip, I believe that these modded T50RP are excellent bargains.

To find more info on these T50RP, you can simply google ZMF and FOSTEX.

One final note. In the past few days, as I reach out for a pair of headphones, I was genuinely surprised that I reached out to the Version 1 T50RP rather than the HD650. I'd like to see if I still do that a month from now. No question that these headphones really are superb and the relatively lost cost is a bonus. If these were at the pro shop, I may well have picked these modded T50RP instead of the HD650. As it is now, they do complement each other nicely, tough the price gap between the two is considerable.

UL

Ps: I do wonder how these headphones would perform with angled pads - would the soundstage feel larger? Love to know if anyone has that information.

Also, any recommendation on a small portable DAC/AMP? I'd like to take these on the road with me to hook up to the laptop.

ZMF also sent me some after market cable that has 1/8" termination. As a former electrical engineer, I had always doubted cable differences but after my recent trips to the pro shop, I do believe some cables make a difference. These are not high cost cables but they are a bit different from the stock Fostex cable. These sound more articulate and brighter but the Fostex stock sounds fatter in tone.

Thanks for the review, specially for comparing with the senns.
There are so many versions of sellers with different t50rp mods, and that's one thing holding me from ordering one. It would be great if somebody compared zfm, mad dogs, mayflower electronics and other modded fostex sellers (if it hasn't been done already) Edited by orangecr - 6/15/13 at 10:04pm

Indeed. I talked to someone who had the Mad Dogs (two of them) and the ZMF version 1 is supposed to be more precise, high resolution, and closer to the HE-500. But it would indeed to have a side by side comparision of the various commercially marketed T50RP. Given all the testing I did with other headphones, and getting a sense of the differences, I feel quite comfortable with my own assessment that the ZMF I ended up with really is excellent for what I am looking for. UL

So I got my “Classic” version with Mr. Speakers Alpha pads in the mail today and spent most of the afternoon listening to an eclectic range of music anything from Daft Punk to George Winston. Pretty much every genre I threw at these they performed flawlessly and piano is especially crisp with these phones!!! I have to say these are fantastic and for the price a steal. I also own a pair of Hi-Fi man HE-500′s and in some ways feel that these are a better headphone at obviously a fraction of the cost. I ran these through my Schiit Lyr & Bitfrost and they proved to have a great soundstage. I even plugged them directly in to my IPhone for giggles and they sounded great at obviously a lower volume level. Thanks Zach for the great mod you have come up with.

Been away from this thread due to some family emergencies, only to come back to see that some pads can even improve the bass and sound further? IF these really do not iimpact the transparency, resolution, and speed, but can increase soundstage and bass, that would be incredible. My fear is that further mods will interfere with all the positive qualities that I've grown to really like. I've been taken away from my home the past week and find myself really missing the headphones in a way that I've not missed headphones before. For whatever the reason, the classic version really connected with me and when I listen to music in other ways I miss that nonfatiguing resolution.

So Zack, could you summarize the types of pads that you have used with your mod and the impact of each type of pad?

Again, thanks for providing an amazing pair of cans that really does compete with much higher priced competitors.

My self modded T50rp's have just slightly more bass than my Q701, and definitely have more sub-bass. The mid-range is just slightly warmer than the Q701, but is still a little forward. Up top my T50rp are smoother and more extended than my Q701. They also are definitely not as peaky, and definitely have more sparkle in the very top end.

1. Which pads gives the widest soundstage and are they a considerable improvement ? The only thing I would wish for is a soundstage that is more along the lines of the Sennheiser HD650 but there are fully open headphones.

2. And does one need to tune the T50RP differently if Alpha Pads are the end destination?

1. Which pads gives the widest soundstage and are they a considerable improvement ? The only thing I would wish for is a soundstage that is more along the lines of the Sennheiser HD650 but there are fully open headphones.

2. And does one need to tune the T50RP differently if Alpha Pads are the end destination?

UL

Soundstage is the least of my concerns when it comes to headphones.

But with the Alpha pads there's indeed more of it, compared to the Dog pads.

To me, the sound of the ZMF with Alpha pads is like a cross between the HD 650 and K240 Sextett. Two headphones I regard highly.